121 HWS_USER_ABORT 21 // User has requested to stop the write sequence122 HWS_FAILED_CALIBRATING 22 // Write failed at the beginning of the media (often a media that is poorly supported by the drive)123 HWS_FAILED_FINISHING 23 // Write failed at the end of the media (finalisation is not complete)124 HWS_WRITING 24 // Currently Writing now

Okay I've spent some time trying to check this out and I've managed to confirm errors 122-124 via logs that users have posted but could only find the first type of error 121 reported and not the second.

Signals PM'ed me about this and thinks that this is the way the list was when Fengtao received it from VSO.

He's not sure about the two error 121s but has kindly offered to check this out for us.